package com.itheima.mp.service.Impl;

import cn.hutool.core.bean.BeanUtil;
import cn.hutool.core.collection.CollUtil;
import cn.hutool.core.util.StrUtil;
import com.baomidou.mybatisplus.core.metadata.OrderItem;
import com.baomidou.mybatisplus.extension.plugins.pagination.Page;
import com.baomidou.mybatisplus.extension.service.impl.ServiceImpl;
import com.baomidou.mybatisplus.extension.toolkit.Db;
import com.itheima.mp.domain.dto.PageDTO;
import com.itheima.mp.domain.po.Address;
import com.itheima.mp.domain.po.User;
import com.itheima.mp.domain.query.UserQuery;
import com.itheima.mp.domain.vo.AddressVO;
import com.itheima.mp.domain.vo.UserVO;
import com.itheima.mp.enums.UserStatus;
import com.itheima.mp.mapper.UserMapper;
import com.itheima.mp.service.IUserService;
import org.springframework.stereotype.Service;

import java.util.*;
import java.util.stream.Collectors;

@Service
public class UserServiceImpl extends ServiceImpl<UserMapper, User> implements IUserService {

  /**
   * 扣除用户金额接口
   *
   * @param id
   * @param money
   */
  @Override
  public void deductBalance(Long id, Integer money) {
    // 1.查询用户
    User user = this.getById(id);
    // 2.校验用户状态
    if (user == null || user.getStatus() == UserStatus.FROZEN) {
      throw new RuntimeException("用户状态异常！");
    }
    // 3.校验余额是否充足
    if (user.getBalance() < money) {
      throw new RuntimeException("用户余额不足！");
    }
    // 4.扣减金额
    // baseMapper.deductBalance(id, money);
    int remainBalance = user.getBalance() - money;
    lambdaUpdate()
      .set(User::getBalance, remainBalance)
      .set(remainBalance == 0, User::getStatus, UserStatus.FROZEN)
      .eq(User::getId, id)
      .eq(User::getBalance, user.getBalance())
      .update();
  }

  /**
   * 根据复杂条件查询用户接口
   *
   * @param name
   * @param status
   * @param minBalance
   * @param maxBalance
   * @return
   */
  @Override
  public List<User> queryUsers(String name, Integer status, Integer minBalance, Integer maxBalance) {
    return lambdaQuery()
      .like(name != null, User::getUsername, name)
      .eq(status != null, User::getStatus, status)
      .ge(minBalance != null, User::getBalance, minBalance)
      .le(maxBalance != null, User::getBalance, maxBalance)
      .list();
  }

  /**
   * 根据id查询用户信息和地址信息
   *
   * @param id
   * @return
   */
  @Override
  public UserVO queryUserAndAddressById(Long id) {
    // 1.查询用户
    User user = getById(id);
    if (user == null || user.getStatus() == UserStatus.FROZEN) {
      throw new RuntimeException("用户状态异常！");
    }
    // 2.查询地址
    List<Address> addresses = Db.lambdaQuery(Address.class).eq(Address::getUserId, id).list();
    // 3.封装VO
    // 3.1.转user的PO为VO
    UserVO userVO = BeanUtil.copyProperties(user, UserVO.class);
    // 3.2.转地址VO
    if (CollUtil.isNotEmpty(addresses)) {
      userVO.setAddresses(BeanUtil.copyToList(addresses, AddressVO.class));
    }
    return userVO;
  }

  /**
   * 批量查询用户
   * @param ids
   * @return
   */
  @Override
  public List<UserVO> queryUserAndAddressByIds(List<Long> ids) {
    // 1.查询用户
    List<User> users = listByIds(ids);
    if(CollUtil.isEmpty(users)) {
      return Collections.emptyList();
    }

    // 2.查询地址
    // 2.1.获取用户id集合
    List<Long> userIds = users.stream().map(User::getId).collect(Collectors.toList());
    // 2.2.根据用户id查询地址
    List<Address> addresses = Db.lambdaQuery(Address.class).in(Address::getUserId, userIds).list();
    // 2.3.转换地址VO
    List<AddressVO> addressVOS = BeanUtil.copyToList(addresses, AddressVO.class);
    // 2.4.用户地址集合分组处理，相同用户的放入一个集合（组）中
    Map<Long, List<AddressVO>> addressMap = new HashMap<>();
    if(CollUtil.isNotEmpty(addressVOS)) {
      addressMap = addressVOS.stream().collect(Collectors.groupingBy(AddressVO::getUserId));
    }

    // 3.转换VO返回
    List<UserVO> list = new ArrayList<>(users.size());
    for (User user : users) {
      // 3.1.转换User的PO为VO
      UserVO userVO = BeanUtil.copyProperties(user, UserVO.class);
      list.add(userVO);
      // 3.2.转换地址VO
      userVO.setAddresses(addressMap.get(user.getId()));
    }
    return list;
  }

  @Override
  public PageDTO<UserVO> queryUserPage(UserQuery userQuery) {
    String name = userQuery.getName();
    Integer status = userQuery.getStatus();
    Integer maxBalance = userQuery.getMaxBalance();
    Integer minBalance = userQuery.getMinBalance();
    // 1.构建查询条件
    Page<User> page = userQuery.toMpPageDefaultSortByUpdateTime();

    // 2.分页查询
    Page<User> p = lambdaQuery()
      .like(name != null, User::getUsername, name)
      .eq(status != null, User::getStatus, status)
      .ge(minBalance != null, User::getBalance, minBalance)
      .le(maxBalance != null, User::getBalance, maxBalance)
      .page(page);

    // 3.封装VO结果
    return PageDTO.of(p, user -> {
      // 1.拷贝基础属性
      UserVO vo = BeanUtil.copyProperties(user, UserVO.class);
      // 2.处理特殊逻辑
      vo.setUsername(vo.getUsername().substring(0, vo.getUsername().length() - 2) + "**");
      return vo;
    });
  }
}
